|Name|First operational|Numeral system|Computing mechanism|Programming|Turing complete|
|---|---|---|---|---|---|
|Zuse Z3 (Germany)|May 1941|Binary floating point|Electro-mechanical|Program-controlled by punched 35 mm film stock (but no conditional branch)|In theory (1998)|
|Atanasoff–Berry Computer (US)|1942|Binary|Electronic|Not programmable—single purpose|No|
|Colossus Mark 1 (UK)|February 1944|Binary|Electronic|Program-controlled by patch cables and switches|No|
|Harvard Mark I – IBM ASCC (US)|May 1944|Decimal|Electro-mechanical|Program-controlled by 24-channel punched paper tape (but no conditional branch)|Debatable|
|Colossus Mark 2 (UK)|June 1944|Binary|Electronic|Program-controlled by patch cables and switches|In theory (2011)|
|Zuse Z4 (Germany)|March 1945|Binary floating point|Electro-mechanical|Program-controlled by punched 35 mm film stock|Yes|
|ENIAC (US)|July 1946|Decimal|Electronic|Program-controlled by patch cables and switches|Yes|
|Manchester Small-Scale Experimental Machine (Baby) (UK)|June 1948|Binary|Electronic|Stored-program in Williams cathode ray tube memory|Yes|
|Modified ENIAC (US)|September 1948|Decimal|Electronic|Read-only stored programming mechanism using the Function Tables as program ROM|Yes|
|Manchester Mark 1 (UK)|April 1949|Binary|Electronic|Stored-program in Williams cathode ray tube memory and magnetic drum memory|Yes|
|EDSAC (UK)|May 1949|Binary|Electronic|Stored-program in mercury delay line memory|Yes|
|CSIRAC (Australia)|November 1949|Binary|Electronic|Stored-program in mercury delay line memory|Yes|

Question: how many dates are listed?
Answer: 12